The PIC 10F2xx chips are in a DIP package which is about 6.5mm wide x 9.5mm long x 3.5mm high, or in a 6 lead SOT23 package, which is about 3.0mm wide (overall) x 3.1mm long x 1.3mm high.They have a precision internal oscillator. They can be programmed in cct., using assembler, C or basic. (I believe there is a free C compiler, which will work for these, included in MPLab.)
The only thing I'd get rid of is the 'home brewed programmer,' unless it is based on an ICD2, or PICkit.